1. Field of the Invention
The teachings in accordance with the exemplary embodiments of this invention relate generally to a vibration control interface.
2. Brief Description of Prior Developments
Mechanical vibrators are employed in conventional electronic devices for a variety of purposes. Mobile phones and pagers utilize a mechanical vibrator to provide a vibrating notification of incoming calls or messages. Game controllers utilize a mechanical vibrator to provide the user with a vibratory effect in the controller, to simulate game mechanics, for example. Conventional mechanical vibrators are generally either binary, having a vibratory effect or no vibratory effect, or have very few vibration settings, as few as two or three that vary only in the strength of the vibratory effect.
It is known to provide tactile feedback to displays of mobile devices (See, for example, “Ambient Touch: Designing Tactile Interfaces for Handheld Devices”, Proceedings of CHI, Volume 4, Issue 2, by Poupyrev et al.). Current vibrators are usually driven with a simple step function voltage signal allowing only monotone vibration. Such signals typically exhibit long rise and fall times that provide poor tactile feedback. In addition, even in instances where the vibration effect length matches well the effect's authored length, as when using Immersion Studio by the Immersion Corporation of San Jose, Calif., the vibration effect envelope can deviate substantially from the designed envelope. As a result, generated effects are not in sync with the graphical elements of, for example, games. In addition, due to the inherent nature of pulse width modulation control the produced effects are lacking in sharp definition.
In addition, pulse width modulated (PWM) vibrators used for haptic and tactile purposes typically require real-time response on the order of 5 milliseconds, that cannot be provided using commonly employed mobile terminal operating systems, such as Symbian OS by Symbian Ltd. Even in instances where it is possible to produce a real time response, the resulting vibration effects are typically left blurry.